Cardiorenal Syndrome in a Kidney Transplant Recipient With High-Flow Arteriovenous Fistula and Mycotic Pneumonia

The arteriovenous fistula (AVF) is a preferred access for haemodialysis (HD) in patients with end-stage renal disease. However, its haemodynamic effect on the heart is not negligible; it may cause or exacerbate heart failure and pulmonary hypertension, especially when the flow is excessively high. After the transplantation, a decrease in cardiac output leads to reduced kidney graft perfusion, which can result in the development of cardiorenal syndrome. The guidelines for managing AVF after transplantation are still not well defined, so care and surveillance are based on the experience of transplantation centres. We present a case of a kidney transplant recipient with deterioration of graft function and sepsis. He received a kidney graft in 2005, and since then, he has had a functioning enlarged AVF, which has not been used since the transplantation. At the time of admission, the flow through the fistula exceeded 7000 mL/min. Blood culture results suggested Staphylococcus haemolyticus as the causative pathogen. The patient was treated with a prolonged course of meropenem and vancomycin based on the antibiogram. Due to radiological findings suggestive of mycotic pneumonia, voriconazole was added. Because of cardiac failure, he was disqualified from surgical treatment of the mycotic pneumonia. He required repeated HD and ultrafiltration for a month using a non-tunnelled catheter. To treat cardiac insufficiency and improve graft function, the fistula was surgically removed. After the surgery, the patient no longer required HD, and his serum creatinine concentration decreased. This case demonstrates that graft function might be restored even after prolonged HD. Therefore, the decision whether to discontinue immunosuppressive therapy to treat the infection must be made carefully. Ligation of a high-flow AVF may contribute to the treatment of cardiac insufficiency, thereby improving graft function. AVF should be monitored regularly to prevent its adverse effects on both cardiac and graft function, which could complicate the management of emerging conditions, as in this case, mycotic pneumonia.